Film core retaining and driving device



April 25, 1950 c. H. JACOBSON 2,505,329 FILM CQRE RETAINING AND DRIVING DEVICE Filed June 28, 1947 Fig.2.

Fig. 5.

INVENTOR Curl H. Jacobson ATTO R N EY Patented Apr. 25, 1950 Carl H:-Jaeobson,- Binghamton; -N-. Y; assiginor-to qeneral Aniline, 8;; Film Corporation, New York," N; Y.,,.a corporation .of Delaware.

ApplicatiGn Jiir-ie 28; 1947, Serial Norma-19 5. oiaims.

This inventionvpertainse to improvements-i in: photographic? apparatus; andmores-specifically;

to"im-proveds-meansrfor driving aafiln'r rolleholding' core onespootland .:for permitting: ready attachment and, detachment thered:

Among the-"objects fofsthc inventionis that of providing *anrwinteroonnelcting means between film core" and its "drivingwspindle which; permits the-coreto be quicklyattached:ands detached; out: which-shall :fwrction: =when:'-assembled,: to ro-' tate': the coret -either posittvely or frictionally th-a"case=may bee It is another object of-the invention ;t.o;de 1ise a -'mechanism-' ot: simpleiconstruction; which may bet"-cheaply manuiacturedr and which shall: be positive in itsaotiom and effective for-*thepurpose described. 'Other objectswillbe apparent from thefollowing" disclosure;

In moving picture apparatus}: e; g: cameras;

projectors" or ina'gazinesiforcameras; film is'reeled cores either ofmtal orplastic; and'these cores; mustbeiquickly iIISELtGdEflI'iGTIBHIOVGdH The-core drivem? preferably byrfrictional engagement; so that-its speediofrotationinlay-varyimaccordance with the amount 5 of' film "available? for being;

wound *or taken *up'.=-* These: requirements calf for zsom'e'interconnection between *the core and a driving?- spindleor'other driving-means;- which will? serve the dual function" of;permitting"ready atetachmentandremoval" and of imparting torque to-theacore:*- Inmost ot-the prior art, the friction drive-*me'ans is which theco're is'i supported and by which it is frictionally retained. According to the present invention, the core its'elf nasattached thereto acoil--of spring wirelor equivalent-which may or may not be positively fixed to the: core; dependaing upon whether or not the drivemeans is to be frictional to compensate for different diameters of film rolLas is customary in 6st take-up mecca-' men-s5 This spring wire cased iii- -sucha messenthat at the- -center-* of l ttle core' 'afid' in position to engagea; driv-ing; ;;spind1e, it is helically formed to be received upon a threaded end oithe'drive means. V

Theinvntionwill-be descr'ibed in greater detail by reference to the accompanying figures of drawing, in which identical reference numerals refer to like parts. In the figures:

Fig. 1 is a perspective view of a film core and a driving means therefor to which the invention has been applied, part of the device having been broken away to be shown in section;

Fig. 2 is a partial section of the core supportpart oi-the-meohanism+ upon ing sleeveand the'drivine core r and: spindle rand?- Fig. 3 is a perspective :viewof theinterconnccting "wire; driving member-s Now, referring to the figures, the invention has been illustratectasit'is appliedztofatypical"movin g pioture apparatus," although it I is -tobeun-- derstood-that a preferredform-only-is illustrated:

and thatthei devices-may be applied to other moving-picture mechanisms and may; take di'fier ent specific-forms without departing from the: originar conceptx- Core; H]. of either metal or plastic is of: more onless conventional. construe tiorn generally-andrha's the: usual; filmeretainingg clipl i; This-core; isv'freelyrotatableppon a supporting sleeve 12, which-is:permanently or otherwise attached tor arwall member -I 3- which may be one: wallaof a film magazine or may" be part o-f-the' casing structure of a camera or pro+ jector; For driving-or-rotating the core, a central spindle 'M-projectsr-throughthesleeve 1,2 and has either as amintegral part thereof or attached as aseparate piecef a:idrive gear-l5 which may be rotated by interconnection? to any conventional power mechanism, such as an electric motor or 25 spring'm'otor'to be found in motion picture apparatus I of this: 'type; 1

The drive spindle 14 projects-beyond the sleeve tit-andalso beyond the face 16 of the iilm core and: terminates-in a-threaded 'end IT. This threaded-end'imay Ice-tapered; as illustrated, or may beof cylindrical form-,- althou'gh thetapered construction is preferred since i it facilitates engagement of the parts when the--core isplaced' on the sleeve:

As shown in Figssland 3,- a wire or other interconnecting drive memberhas a portion l8 whichis'insertable in a groove, 19 cut-at the base of flange 20 in the core. The part 180i the-wire coil member is. practically: I circularin form and extends for*sli'ghtly' more than 180; so that it functions "as asnaprwir'e inthe, groove and thusmay be quickly :attachedzor detached; The wire is then coiled inwardlwtoward the center at 2 i and-terminates in ahelical-'portionsfl which may 5 betapering, as"i11ustrated','to-be threaded onto thepart" I? of the'drive spindle"; or may be of other-"shape; depending'upon' thexsaid threaded part oithe spindle: Whileany convenient num' 22 is such that when the spindle I4 is rotated in the driving direction, the threaded engagement will tend to become more tightened. To disassemble the parts it is only necessary to rotate the core in the opposite direction for three turns more or less, depending upon the number of threads l1, and it may be readily detached. If the tapering is pronounced, fewer turns are necessary for effecting engagement and disengagement.

The frictional contact between the part of the wire l8 and the groove I9 is regulated to impart the requisite torsional force for winding film on the core. As is commonly practiced in most take-up drives, the spindle I always rotates much faster than the core at the start of winding and slightly faster than the core when the latter has been filled. In some instances, it may be desired to drive positively and in that event, the spring wire may be fixed to the core by soldering in the event the'parts are of metal, or may be so formed as to engage a part of the core in such a manner that it cannot be rotated relatively thereto.

While the interconnecting driving means has specifically been referred to as a spring wire, it i to be understood that other equivalents are contemplated and that flexibility is not necessary in all instances. Something other than wire may be employed, if desired. The actual form of the core may be varied within wide limits and the term core is to be understood as being generic to all types of film roll-holding apparatus, for example, reels or other flanged members commonly employed for winding film.

While one preferred embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This application is, therefore, not to be limited to the precise details described, but is intended to cover all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

I claim:

1. In a photographic device having a film core and a supporting member upon which said core is freely rotatable and from which it may be readily detached, means for rotating said core when assembled on said supporting member and for retaining it in position axially thereof, which comprises a driven member threaded at one end and a wire spring member having at one end driving engagement with the core and at its other end being helically coiled to be drivingly engaged upon the threaded end of said driven member upon relative rotation in one direction and to be disengaged therefrom upon rotation in the opposite direction.

2. In a photographic device having a film core and a supporting member upon which said core is freely rotatable and from which it may be readily detached, means for rotating said core when assembled on said supporting member and for retaining it in position axially thereof, which comprises a driven spindle carried within and extending beyond said supporting member, that end which extends beyond the supporting member being threaded, and an interconnecting and torque transmitting member helically coiled at one end for engagement with the threaded end of the spindle and frictionally attached at its other end to the core.

3. In a photographic device having a film core and a supporting member upon which said core is freely rotatable and from which it may be readily detached, means for rotating said core when assembled on said supporting member and for retaining it in position axially thereof, which comprises a driven spindle carried within and extending beyond said supporting member, that end which extends beyond the supporting member being tapered and threaded, and an interconnecting and torque transmitting wire member helically coiled at one end to engage the threaded end of the spindle and having a snap ring connection with the core at its other end.

4. In a photographic device having a film core and a supporting member upon which said core is freely rotatable and from which it may be readilydetached, means for rotating said core when assembled on said supporting member and for retaining it in position axially thereof, which comprises a driven spindle carried within and extending beyond said supporting member, that end which extends beyond the supporting member being tapered and threaded, and an interconnecting and torque transmitting wire member helically coiled at one end to engage the threaded end of the spindle and at its other end having a concentric portion extending circumferentially for more than for engagement within a groove in the core, said concentric portion being curved to a radius greater than that of the coreto provide snap engagement and frictional driving contact between the parts.

5. In a photographic device having a film core and a relatively fixed sleeve upon which said core is freely rotatable and'from which it may be readily detached, a driven spindle guided within and having a tapered, threaded end projecting beyond said sleeve, and interconnecting torque transmitting means between said spindle and core which comprises a spring wire member having a tapered, helically coiled end for engagement upon the threaded end of the spindle and at its other end having a concentric portion extending circumferentially for more than 180 for engagement within a groove in the core, said concentric portion being curved to a radius greater than that of the core to provide snap engagement and frictional driving contact between the parts.

CARL H. JACOBSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,111,506 Tessier Sept. 22, 1914 2,424,697 Lear July 29, 1947 FOREIGN PATENTS Number Country Date 546,256 Germany Mar. 11, 1932 

